Wi-Fi is considered to be one of the most important wireless data communication methods for mobile devices. In recent years, Wi-Fi has held higher importance in smart devices since it is being touted as the only alternative which can offload the deluge of mobile data rapidly saturating the capacity limit of cellular networks [4]. Several studies [5, 10] have stated that by the year 2014, up to 70% of the data generated by smart devices can be offloaded to Wi-Fi networks if the data to be offloaded can tolerate a certain amount of delay until the smart device moves into a Wi-Fi coverage area. Despite its capabilities, high energy consumption by Wi-Fi is a critical drawback in smart devices. According to [19], Wi-Fi consumes around 20% of the total power used by a smart phone even if the Wi-Fi radio is in idle state. Similarly, measurements indicate that web browsing through Wi-Fi consumes around 30% to 47% of power for various smart phones while the remaining significant portion of power is consumed by displays (LCD, OLED) and display back lights. The topic on energy savings for Wi-Fi has interested the research community for years, and, as a result, several different approaches to reduce the Wi-Fi power consumption have been proposed. These approaches include extending the duration of power saving mode (PSM), reducing the idle state listening power and removing the repeated triggering of Wi-Fi scans when the location is determined to have no Wi-Fi access point (AP).
Among many directions for saving Wi-Fi energy consumption, the subject matter described herein focuses on energy consumption in Wi-Fi scans. Given default operation triggering Wi-Fi scans whenever the display is turned on in most smart devices, energy consumption due to Wi-Fi scans is already non-trivial. However, the energy consumption due to Wi-Fi scans can become much more serious when use of cloud services by smart devices is considered. Cloud services, such as iCloud from Apple [1] attempts to synchronize data in a smart device with a remote server. Perfect synchronization requires that all synchronizations occur immediately whenever a change in data is detected, but this could severely burden cellular networks with data traffic. Hence, a viable solution will be to offload this synchronization burden to Wi-Fi networks [10]. For example, a video file recorded in a national park by the smart device can be synchronized to a cloud server whenever the device detects opportunities to connect to Wi-Fi networks while the user is returning back home so that he/she can watch the video through a TV connected to the cloud server. The question here is how to efficiently maximize the opportunities to offload data to Wi-Fi networks since continuous scanning of Wi-Fi APs is obviously not the best solution. A more interesting question can be how to maximally discover Wi-Fi APs with minimal power consumption. Given that the amount of power consumption of Wi-Fi during scan state is comparable to that of transmission state [19], this question appears to be challenging.
Accordingly, in light of these difficulties, there exists a need for methods, systems, and computer readable media for reducing Wi-Fi scanning using cellular network to Wi-Fi access point mapping information.